How to update HTC One M7 to Android 5.1 Lollipop with CyanogenMod 12.1 ROM.XDA

HTC vice president of product management, Mo Versi has confirmed that only the Google Play Edition of One M7 will receive Android 5.1, leaving the Sense version of the device on Android 5.0.2.

But thanks are due to the Android developer community for continuing development with several custom builds based on Android Lollipop.

Recently, senior XDA member, AndroidGeek974 has made an unofficial build of CyaogenMod 12.1 featuring Google's latest Android Lollipop version. Almost all features seem to be working fine in the build, confirms the developer. But there might be some bugs since this is still in the beta version. Head over to the development thread to know more about the beta CyanogenMod 12.1 version.

ROM info

ROM OS version: 5.1.x Lollipop

ROM kernel: Linux 3.4.x

Status: Beta

Created: 5 April

Important points

Before following the installation guide, create a backup of all important data of the phone using custom recovery.

Enable USB Debugging on the phone to connect it with the computer and use Android SDK with it. [Navigate to Settings>> About phone. Tap on Build Number several times until a message appears saying 'You are now a Developer.' Now enable USB Debugging Mode by navigating to Settings>> Developer Options.]

Your One M7 should have above 80% battery charge to avoid power off during the process which could damage the device.

The phone should be rooted with the latest recovery system installed on it. Also, it should have an unlocked bootloader. [The guide below uses TWRP recovery.]

As the CyanogenMod 12.1 ROM is in its testing stage; all the features might not function properly.

The Android 5.1 CyanogenMod 12.1 ROM works with first generation HTC One M7 only. Flashing this on any incorrect variant might brick the device. Therefore, verify the model number of the device.

After flashing the ROM if the device gets stuck on the booting animation or if you experience boot loop then perform wipe cache partition and wipe dalvik cache for a few times before rebooting the device.

Once the ROM is installed, users are advised to give 10 minutes to the ROM after the device boots up for the first time for better user experience.